How Electromagnetic Flowmeters Work

Electromagnetic flowmeters, also known as magnetic flowmeters or magmeters, use Faraday’s Law of Electromagnetic Induction to determine the flow of liquid in a pipe. In an electromagnetic flowmeter, a magnetic field is generated and channeled into the liquid flowing through the pipe. Following Faraday’s Law, flow of a conductive liquid through the magnetic field will cause a voltage signal to be sensed by electrodes located on the flow tube walls. When the fluid moves faster, more voltage is generated. Faraday’s Law states that the voltage generated is proportional to the movement of the flowing liquid. The electronic transmitter processes the voltage signal to determine liquid flow.

In contrast with many other flowmeter technologies, electromagnetic flowmeter technology produces signals that are linear with flow. As such, the turndown associated with magnetic flowmeters can approach 20:1 or better without sacrificing accuracy. Continue reading “How Electromagnetic Flowmeters Work”

Infrared Thermometers

Dwyer offers several temperature measuring products that use infrared sensors as the sensing element.


Infrared Thermometers infer the temperature of an object by measuring the infrared thermal radiation emitted from the object. Objects at thermal equilibrium must balance the energy that is entering the object with the energy that is leaving the object.  Often, the energy leaving the object is emitted as electromagnetic radiation. Continue reading “Infrared Thermometers”